Metals such as tungsten (W), zinc (Zn), copper (Cu), cobalt (Co), iron (Fe), nickel (Ni) and manganese (Mn) all have the ability to catalyze oxidation and reduction reactions, but of these only Fe, Zn, Cu and Mn are likely to be present in wine at concentrations high enough to have a significant effect.1 Aluminium (Al) has also been shown to be important in limiting oxygen consumption in wine.7 Se